1. Field of the Invention
The present invention relates to an improvement in the exchange of heat between two airstreams through the provision of plate-type crossflow air-to-air heat exchangers having a series of parallel channels alternately blocked and enclosed in a housing which forces one airstream to be directed through the exhaust air channels and a second airstream to be directed through the supply air channels, in substantially crossflow arrangement, for the exchange of heat.
The invention further includes the provision of arranging a number of the heat exchanger units side-by-side with a manifold to disperse and gather the related airstreams to a plenum chamber to reduce the size of the system and the energy requirements for operating the system to condition a large volume of air.
2. Discussion of the Prior Art
Fresh-air for residences and buildings is needed to maintain proper indoor air quality. This fresh-air must be heated or cooled, depending on weather conditions and this typically requires relatively large amounts of energy. Devices that exchange heat between airstreams are well known, whereby the stale air being exhausted from a building serves as the energy source for heating or cooling incoming outside air.
In the prior art, there exists a number of crossflow plate type air-to-air heat exchangers. These heat exchange devices may be constructed of plastic or metal for sensible heat exchange or they can be constructed of homogenous material such as paper for sensible and latent energy exchange.
In the prior art heat exchangers there is generally required a large space to house the large plate cross flow heat exchanger. As the plates of a plate heat exchanger increase in size, for a given efficiency, the spacing between the plate's increase in distance. This increase in plate spacing accounts for significant increase in the size of the apparatus.
Volumetric efficiency quantifies the required equipment volume in per unit of capacity at a given performance level. In plate-type crossbow air-to-air heat exchangers, to increase the volumetric efficiency and economy of the unit the smallest possible plate size should be used. However, crossflow heat exchangers with smaller plates generally require more length, i.e. more plates, to handle air volumes equal to that of units with larger plates. Increasing the plate size will require a larger installation space, which may limit the performance of the heat exchanger. In addition, when using crossflow plate-type air-to-air heat exchangers with smaller plates, the length, or number of plates, typically exceeds the allowable dimension or number of plates.
The novel heat exchanger of the present invention obviates the disadvantages associated with the prior art, by providing a plate-type crossbow air-to-air heat exchanger having a plurality of plates while maintaining a seal between the intake channels and exhaust channels as will be described below. The heat exchanger of the present invention also facilitates installation in a system which utilizes a number of small units to reduce the size required for installation, and ultimately provide an efficiently operating and economical system for recovering heat in buildings such as homes and offices.